Olaparib In Patients Research Articles

A clinical study of tremelimumab alone or in combination with olaparib in patients with advanced epithelial ovarian cancer.

6045 Background: Single agent immunotherapy (IO) has shown only modest clinical activity for the treatment of ovarian cancer. The combination of anti-programmed death-1 and PARP inhibitors showed promising activity in early trials. Here, we report the results of an open-label, parallel arm, dose escalation study of tremelimumab (T) alone or in combination with olaparib (O) in patients (pts) with advanced epithelial ovarian cancer (EOC). Methods: Pts with recurrent/persistent EOC who had progression < 12 months from last platinum exposure were enrolled. Prior therapy with IO (except anti-CTLA-4) or PARP inhibitor was allowed. Pts were randomized to either T 10mg/kg every 4 weeks (wks) x 7 then every 12 wks (Arm A) or T with O twice daily at three planned dose levels (Arm B). The primary objectives were safety, pharmacodynamic (PD) change in CD4+ICOShi peripheral T cells by flow cytometry, and identification of the optimal dose combination of T with O. Secondary objectives included 6-month progression-free survival (PFS6) and objective response rate (ORR). Results: A total of 24 pts were treated, 12 on Arm A, and 12 on two Arm B dose levels. Pts had a median age of 60 years (range 44-81). Histologic subtypes included high-grade serous EOC (20 pts, 83%), clear cell (3 pts, 13%), and moderately-differentiated adenocarcinoma (1 pt, 4%). BRCA1 mutation (mt) was present in 2 cases, BRCA2 mt in 1. Median number of prior regimens was 3.5 (range 1-9). Most adverse events (AEs) were attributable to T, the most common grade 3 toxicities were rash (13%), immune-mediated hepatitis (8%), and colitis (8%). No grade ≥4 toxicities were identified. Immune-mediated AEs also included acute kidney injury, hypophysitis, and hypothyroidism. No dose limiting toxicities were identified on Arm B. Two pts in Arm B had >PFS6. Of 20 pts evaluable for response, there was 1 partial response (Arm B), and 9 pts had stable disease (6 on Arm A, 3 on Arm B). Mean percentage of CD4+ICOShi T cells was significantly increased on Days 15 and 22 compared to Day 1 at both T dose levels (Table).T at 3 mg/kg with O at 150mg is the optimal dose of those tested. Conclusions: T and T with O was tolerable, with modest clinical activity in this pt population. AEs were as expected, and peripheral CD4+ICOShi T cells increased on therapy. Clinical trial information: 02485990. [Table: see text]

Preliminary efficacy data of triple-negative breast cancer cohort of NCI 9881 study: A phase II study of cediranib in combination with olaparib in advanced solid tumors.

1077 Background: Cediranib, a pan-vascular endothelial growth factor receptor tyrosine kinase inhibitor, suppresses expression of BRCA1, BRCA2, and RAD51 and increases sensitivity of tumors to poly-(ADP-ribose) polymerase (PARP) inhibitors in vitro. Olaparib, a PARP inhibitor, demonstrates clinical efficacy in patients with germline BRCA1/2 mutations and HER2-negative metastatic breast cancer. We therefore tested the anti-tumor activity of the combination of cediranib and olaparib in patients (pts) with metastatic triple-negative breast cancer (TNBC). Methods: This multi-institutional, two-stage, phase II study enrolled patients with metastatic TNBC previously treated with a minimum of one prior line of systemic therapy in the advanced setting. Patients were treated with cediranib 30mg po daily plus olaparib 200mg po BID until disease progression or unacceptable toxicity. The primary endpoint was objective response rate by RECIST v1.1. Baseline tumor biopsies were obtained for biomarker analyses. Results: Baseline characteristics of the 37pts enrolled are summarized below. The overall objective response rate was 14% (95% CI: 0.025, 0.2453). Median duration of response was 2.0 months (mos) with a range of 1.8 to 6.3 mos. Disease control rate ((# of pts with CR, PR or SD)/(# of evaluable pts)) was 81% (95% CI: 0.6846, 0.937). Median PFS was 3.7 mos (95% CI: 2.1, 4.3). Grade 3/4 adverse events (G3/4 AEs), irrespective of attribution, occurred in 25 of 38 (66%).G3/4 AEs occurring in > 5% of pts were hypertension (24%) and dyspnea (11%), diarrhea (8%) vomiting (8%). Conclusions: The cediranib/olaparib combination resulted in promising objective responses in 14% of biomarker-unselected patients with heavily pre-treated, metastatic TNBC. The regimen required prompt initiation of antihypertensives, but AEs were overall manageable. Analyses of mutation status in homologous recombination DNA repair genes are ongoing and will be correlated with clinical outcome. Clinical trial information: NCT02498613 . [Table: see text]

Phase II study of olaparib in malignant mesothelioma (MM) to correlate efficacy with germline and somatic mutations in DNA repair genes.

9054 Background: BRCA1 associated protein 1 ( BAP1), a nuclear deubiquitinase involved in DNA double-strand break repair is frequently mutated in MM. Because poly(ADP-ribose) polymerase inhibitors (PARPIs) induce synthetic lethality in BRCA1/2 mutant cancers, we sought to evaluate efficacy of olaparib in patients with MM and correlate it with pathogenic germline and somatic mutations in DNA repair genes. Methods: Phase II single-center study (NCT03531840) enrolled patients with advanced pleural or peritoneal mesothelioma who had progressed on prior therapies, age >18 years, ECOG performance status <1, adequate organ and bone marrow function. Olaparib 300mg was given twice daily orally in 3 week cycles until disease progression or toxicity. Efficacy was assessed by CT scan every 6 weeks using RECIST criteria. Whole exome sequencing (WES) was performed on blood and tumor samples to identify pathogenic germline and somatic mutations in DNA repair genes. Primary objective was to determine response rate based on germline or somatic mutation status of DNA repair genes. Results: Between July 2018 to May 2019, 23 patients were enrolled, 15 pleural and 8 peritoneal MM [14 male; median age 63 (range 41-75 years); median number of prior treatments 3 (range 1-5)]. Median olaparib cycles received was 4 (2-21). WES to identify pathogenic mutations in the germline and tumor was performed in 23 and 17 patients respectively. Four patients had germline BAP1, 1 germline MRE11A, and 5 had somatic BAP1 mutations. Of 22 evaluable patients, 1(4%) had partial response (PR), 17 (77%) had stable disease at 6 weeks and 4 (18%) had progressive disease. Patient with PR had a germline mutation in MRE11A. Median progression free survival (PFS) and overall survival (OS) for all patients was 3.4 months (95% CI: 2.7 – 4.8 months) and 8.1 months (95% CI: 4.5 months – not estimable) respectively. Median PFS of germline BAP1 mutant patients (n = 4) was 2.3 months (95% CI: 1.3 – 3.6 months) compared to 4.1 months (95% CI: 2.7 – 5.5 months) for BAP1wild type patients (n = 18;P = 0.026). Median OS was 4.6 months (95% CI: 3.1 – 4.9 months) for patients with germline BAP1 mutation versus not reached for those without germline BAP1 mutation (P = 0.0058). The most common side effects of olaparib were anemia (16%), lymphopenia (24%), nausea (14%), and increased creatinine (9%). Conclusions: Olaparib has limited anti-tumor activity in previously treated MM patients including those with germline or somatic BAP1 mutations. Presence of germline BAP1 mutations was associated with decreased PFS and OS. Clinical trial information: NCT03531840.

Cediranib in combination with olaparib in patients without a germline BRCA1/2 mutation with recurrent platinum-resistant ovarian cancer: Phase IIb CONCERTO trial.

6056 Background: A Phase I trial (NCT01116648) of cediranib (cedi) in combination with olaparib (ola) (cedi + ola) demonstrated an overall response rate of 44% in patients (pts) with recurrent ovarian cancer (OC), including pts without a deleterious or suspected deleterious gBRCAm (non-gBRCAm; Liu et al. Eur J Cancer 2013). The subsequent Phase II trial (NCT01116648) showed significant improvement in progression-free survival (PFS) with cedi + ola versus ola monotherapy in recurrent platinum-sensitive OC pts, notably in non-gBRCAm pts (Liu et al. Lancet Oncol 2014). We report data from the Phase IIb, single-arm, open-label CONCERTO study investigating cedi + ola in non-gBRCAm pts with recurrent platinum-resistant OC who had received ≥3 previous lines of therapy for advanced OC (NCT02889900). Methods: Pts with disease progression <6 months from the last receipt of platinum-based chemotherapy received cedi tablets (30 mg once daily) plus ola tablets (200 mg twice daily) until progression or unacceptable toxicity. gBRCAm pts were ineligible. Primary endpoint: objective response rate (ORR) by independent central review (ICR; RECIST 1.1). Key secondary endpoints: PFS and safety. Results: 60 pts from the USA were included (median age: 64.5 years; median number of previous systemic treatment regimens: 4 [range: 2–9]; previous bevacizumab: 53). All pts had high-grade OC (90% serous; 3.3% clear cell; 3.3% endometrioid; 3.3% other). 7% of pts had tumor BRCA2 (confirmed somatic) mutations, 80% of pts had no tumor BRCA mutation (non-tBRCAm) and 13% of pts were not evaluable for tBRCAm. Five (8%) pts who were non-tBRCAm carried somatic homologous recombination repair gene mutations (FoundationOne Clinical Trial Assay, Foundation Medicine, Inc). The Table shows results of key endpoints. Most common grade ≥3 adverse events (AEs) that occurred in pts were hypertension (30%), fatigue (22%) and diarrhea (13%). 37% of pts reported serious AEs, of which nausea (7%) was most common. Dose interruptions, reductions and discontinuations were caused by AEs in 55%, 18% and 18% of pts, respectively, who received cedi + ola. Conclusions: Cedi + ola showed evidence of antitumor activity in heavily pretreated non-gBRCAm pts with recurrent platinum-resistant OC. Toxicity was manageable with dose modifications. Clinical trial information: NCT02889900. [Table: see text]

POLO: Radiologic assessment of the impact of maintenance olaparib in patients (pts) with metastatic pancreatic cancer (mPaC).

e16800 Background: The Phase III POLO study (NCT02184195) demonstrated a benefit of maintenance olaparib over placebo in the radiologically assessed primary endpoint of progression-free survival (PFS) in pts with mPaC (median 7.4 vs 3.8 months [mo]; 12-mo rate 34% vs 15%). The impact of radiologic assessment of pancreatic lesions, which is considered challenging, was explored. Methods: Tumors were assessed using Response Evaluation Criteria in Solid Tumors version 1.1 by blinded independent central review (BICR) in pts with mPaC treated with maintenance olaparib or placebo. PFS was analyzed in subsets of pts based on various event criteria. Results: All 154 randomized pts had mPaC prior to chemotherapy, of whom 122 had disease in the pancreas at POLO baseline (BL); 34% (53/154) had pancreas-only target lesions (TL), 26% (40/154) also had ≥1 TL outside of the pancreas, and in 19% (29/154) pancreatic disease was recorded as non-TL. Sensitivity analyses were consistent with the primary PFS analysis (Table), including when all pancreas lesion assessments were discounted (median PFS 7.4 vs 4.7 mo; 12-mo rate 38% vs 22%). Of 53 pts with pancreas-only TLs at BL, 34 had disease progression (PD); in 20 pts this was not solely based on TL measurements (16 had new lesions; 4 had multiple-cause PD). Confirmed objective responses occurred during study maintenance treatment in 20% of olaparib pts (18/92) and 10% of placebo pts (6/62). In pts with pancreas-only TLs at BL there were 7 responses in the olaparib arm (1 complete response [CR], 6 partial responses [PR]) and 2 (2 PR) in the placebo arm. In pts who had ≥1 TL outside of the pancreas at BL there were 11 (1 CR, 10 PR) and 4 (4 PR) responses, respectively. Responses were generally durable irrespective of TL location. Conclusions: The significant PFS benefit with maintenance olaparib over placebo shown in the primary analysis was consistent across all sensitivity analyses and was not impacted by radiologic assessment of pancreatic TLs. Taken together, these findings suggest that contrary to historically held belief, primary pancreas TLs may be appropriate for inclusion as sites of RECIST-evaluable disease and for assessment of treatment outcome. Clinical trial information: NCT02184195 . [Table: see text]

Final overall survival (OS) results from SOLO2/ENGOT-ov21: A phase III trial assessing maintenance olaparib in patients (pts) with platinum-sensitive, relapsed ovarian cancer and a BRCA mutation.

6002 Background: SOLO2 (ENGOT ov-21; NCT01874353) showed that maintenance therapy with the PARP inhibitor olaparib in pts with platinum-sensitive relapsed ovarian cancer (PSROC) and a BRCA mutation (BRCAm) led to a statistically significant improvement in median progression-free survival (PFS) of 13.6 months vs placebo (hazard ratio [HR] 0.30). Time to second progression or death significantly improved (Pujade-Lauraine et al Lancet Oncol 2017) and a quality-adjusted PFS benefit was seen (Friedlander et al Lancet Oncol 2018) with maintenance olaparib vs placebo. We report the preplanned final OS analysis for SOLO2. Methods: Pts with PSROC and a BRCAm who had received ≥2 lines of treatment and were in response to their most recent platinum-based chemotherapy received maintenance olaparib (300 mg bid tablets) or placebo. Pts were stratified by response to previous chemotherapy (complete vs partial) and length of platinum-free interval (>6–12 months vs >12 months). OS was a secondary endpoint. The only preplanned OS sensitivity analysis was an OS analysis in the Myriad germline BRCAm subset (Myriad BRAC Analysis test). Results: At final data cut-off (Feb 3, 2020), median follow-up was 65 months in both treatment arms. A long-term treatment benefit was seen with olaparib vs placebo with an OS HR of 0.74 (95% confidence interval [CI] 0.54–1.00) in the full analysis set (FAS; unadjusted for crossover; 38.4% of placebo pts crossed over to a PARP inhibitor) (Table). At 5 years: by Kaplan-Meier estimates, 28.3% of pts in the olaparib arm vs 12.8% of pts in the placebo arm were alive and had still not received subsequent treatment; 42.1% of olaparib pts vs 33.2% of placebo pts were alive. The long-term tolerability profile of olaparib was generally consistent with that reported previously. Conclusions: In the final analysis of SOLO2, maintenance olaparib provided an unprecedented improvement of 12.9 months in median OS vs placebo. This is the first study with olaparib tablets, and the first since Study 19 (NCT00753545), to provide long-term follow-up and final OS data in pts with PSROC and a BRCAm. Clinical trial information: NCT01874353. [Table: see text]

Pembrolizumab (pembro) plus olaparib in patients (pts) with docetaxel-pretreated metastatic castration-resistant prostate cancer (mCRPC): KEYNOTE-365 cohort A efficacy, safety, and biomarker results.

5544 Background: Pembro + olaparib has shown antitumor activity and acceptable safety in docetaxel-pretreated pts with mCRPC enrolled in cohort A of the phase I/II KEYNOTE-365 study (NCT02861573). Updated results with new biomarker data are reported. Methods: Pts with docetaxel-pretreated mCRPC who progressed within 6 mo of screening received pembro 200 mg IV Q3W + olaparib 400-mg capsule or 300-mg tablet PO BID. Pts might have received 1 other chemotherapy and ≤2 second-generation androgen-receptor targeted therapies. Primary end points: PSA response rate (decrease ≥50% from baseline, confirmed by a second value ≥3 wks later), ORR per RECIST v1.1, and safety. Key secondary end points: DCR, DOR, rPFS, and OS. Biospecimens (eg, blood, tissue) were collected for biomarker analysis (tissue PD-L1 expression, androgen receptor variant 7 [AR-v7] expression in circulating tumor cells [CTCs], and a T-cell–inflamed gene expression profile [GEP]). ctDNA was analyzed by Guardant Health 360 (GH360) and Omni (GH Omni) assays. FFPE tissue was analyzed by FoundationOne CDx (F1CDx) assay. Results: 84 of 87 enrolled pts were treated; 48/84 (57.1%) had measurable disease. Median (range) time from enrollment to data cutoff was 3.6 mo (0.0-29.2) for all pts and 26.7 mo (21.2-29.2) for 41 pts with ≥27 wks’ follow-up. Confirmed PSA response rate was 9% (95% CI, 3.5-16.8) in 82 pts with a baseline PSA assessment. Median time to PSA progression: 3.8 mo (95% CI, 2.9-4.4). In 24 pts with measurable disease and ≥27 wks’ follow-up, ORR was 8.3% (95% CI, 1.0-27.0; 2 PRs) and DCR ≥6 mo was 20.8% (95% CI, 7.1-42.2). Median (range) DOR was NR (12.0+ to 21.4+ mo); 2 pts had DOR ≥12 mo. In all pts, median rPFS was 4.3 mo (95% CI, 3.4-7.7) and median OS was 14.4 mo (95% CI, 8.1-18.5). Grade ≥3 TRAEs occurred in 29 pts (35%); 2 pts died of TRAEs (1 myocardial infarction, 1 unknown). Overall, 26% had PD-L1+ tumors (combined positive score ≥1). Of 31 pts with CTC data, 12.9% were AR-v7+. No BRCA1/2 mutation was detected by GH360 (n=42). Of 57 pts analyzed by GH Omni, 2 had BRCA2 mutations, 1 had a BRCA1 mutation, 4 had ATM mutations, 1 had a CHEK1 mutation, and 6 had CDK12 mutations. Of 49 pts analyzed by F1CDx, 4 had BRCA mutations; 1 pt had a copy number loss mutation not detected by ctDNA analysis. GEP was not associated with ORR or PSA response. Conclusions: Pembro + olaparib continued to show activity and acceptable safety in pts with docetaxel-pretreated mCRPC. A phase III study of this combination is ongoing (KEYLYNK-010, NCT03834519). Clinical trial information: NCT02861573 .

Pharmacokinetics and safety of olaparib in patients with advanced solid tumours and mild or moderate hepatic impairment.

Olaparib, a potent oral poly(ADP-ribose) polymerase inhibitor, is partially hepatically cleared. We investigated the pharmacokinetics (PK) and safety of olaparib in patients with mild or moderate hepatic impairment to provide dosing recommendations. This Phase I open-label study assessed the PK, safety and tolerability of single doses of olaparib 300-mg tablets in patients with advanced solid tumours. Patients had normal hepatic function (NHF), or mild (MiHI; Child-Pugh class A) or moderate (MoHI; Child-Pugh class B) hepatic impairment. Blood was collected for PK assessments for 96 hours. Patients could continue taking olaparib 300 mg twice daily for long-term safety assessment. Thirty-one patients received ≥1 dose of olaparib and 30 were included in the PK assessment. Patients with MiHI had an area under the curve geometric least-squares mean (GLSmean) ratio of 1.15 (90% confidence interval 0.72, 1.83) and a GLSmean maximum plasma concentration ratio of 1.13 (0.82, 1.56) vs those with NHF. In patients with MoHI, GLSmean ratio for area under the curve was 1.08 (0.66, 1.74) and for maximum plasma concentration was 0.87 (0.63, 1.22) vs those with NHF. For patients with mild or moderate hepatic impairment, no new safety signals were detected. Patients with MiHI or MoHI had no clinically significant changes in exposure to olaparib compared with patients with NHF. The safety profile of olaparib did not differ from a clinically relevant extent between cohorts. No olaparib tablet or capsule dose reductions are required for patients with MiHI or MoHI.

An immune-centric exploration of BRCA1 and BRCA2 germline mutation related breast and ovarian cancers

BackgroundBRCA1/2 germline mutation related cancers are candidates for new immune therapeutic interventions. This study was a hypothesis generating exploration of genomic data collected at diagnosis for 19 patients. The prominent tumor mutation burden (TMB) in hereditary breast and ovarian cancers in this cohort was not correlated with high global immune activity in their microenvironments. More information is needed about the relationship between genomic instability, phenotypes and immune microenvironments of these hereditary tumors in order to find appropriate markers of immune activity and the most effective anticancer immune strategies.MethodsMining and statistical analyses of the original DNA and RNA sequencing data and The Cancer Genome Atlas data were performed. To interpret the data, we have used published literature and web available resources such as Gene Ontology, The Cancer immunome Atlas and the Cancer Research Institute iAtlas.ResultsWe found that BRCA1/2 germline related breast and ovarian cancers do not represent a unique phenotypic identity, but they express a range of phenotypes similar to sporadic cancers. All breast and ovarian BRCA1/2 related tumors are characterized by high homologous recombination deficiency (HRD) and low aneuploidy. Interestingly, all sporadic high grade serous ovarian cancers (HGSOC) and most of the subtypes of triple negative breast cancers (TNBC) also express a high degree of HRD.ConclusionsTMB is not associated with the magnitude of the immune response in hereditary BRCA1/2 related breast and ovarian cancers or in sporadic TNBC and sporadic HGSOC. Hereditary tumors express phenotypes as heterogenous as sporadic tumors with various degree of “BRCAness” and various characteristics of the immune microenvironments. The subtyping criteria developed for sporadic tumors can be applied for the classification of hereditary tumors and possibly also characterization of their immune microenvironment. A high HRD score may be a good candidate biomarker for response to platinum, and potentially PARP-inhibition.Trial registrationPhase I Study of the Oral PI3kinase Inhibitor BKM120 or BYL719 and the Oral PARP Inhibitor Olaparib in Patients With Recurrent TNBC or HGSOC (NCT01623349), first posted on June 20, 2012. The design and the outcome of the clinical trial is not in the scope of this study.

Adverse events (AEs) with maintenance olaparib in patients with a germline BRCA mutation (gBRCAm) and metastatic pancreatic cancer (mPaC): Phase III POLO trial.

686 Background: In POLO (NCT02184195), maintenance olaparib was well tolerated and led to a significant progression-free survival benefit vs placebo in patients with a gBRCAm and mPaC whose disease had not progressed on first-line platinum-based chemotherapy (HR 0.53; 95% CI 0.35–0.82) (Golan et al. NEJM 2019). We analyzed common AEs and their management in POLO. Methods: Patients were randomized (3:2) to maintenance olaparib (tablets; 300 mg bid) or placebo until disease progression or unacceptable toxicity. AEs were graded using CTCAE v4.0. Results: Of 154 randomized patients, 151 were treated (olaparib, n=91; placebo, n=60) and included in safety analyses. Median treatment duration was 6.0 months (m) for olaparib and 3.7 m for placebo. Management of fatigue/asthenia, nausea, anemia and vomiting included supportive treatment and/or dose modification; few patients discontinued treatment due to AEs (Table). Of patients with anemia, 14 olaparib recipients received a blood transfusion while on study treatment; one olaparib recipient received epoetin beta. Conclusions: The AE profile of maintenance olaparib in patients with a gBRCAm and mPaC was consistent with that seen in other tumor types.Common AEs of fatigue/asthenia, nausea, anemia and vomiting occurred early, were manageable and led to few treatment discontinuations. Clinical trial information: NCT02184195 . [Table: see text]

Maintenance therapies in metastatic pancreatic cancer: present and future with a focus on PARP inhibitors.

Metastatic pancreatic ductal adenocarcinomas (PDACs) are now more effectively controlled using chemotherapy combinations such as FOLFIRINOX and gemcitabine plus nab-paclitaxel (NabP) regimens with a subset of patients who achieve a sustained tumor stabilization or response. The next challenge is to design maintenance therapies that result in continued tumor control with minimal toxicity. Quality of life should always be a priority in these patients with prolonged survival. Gradually tapering off the intensity of chemotherapy by suppressing drug(s) in the combination is one option. Thus, maintenance with 5-fluorouracil or gemcitabine as single agents after FOLFIRINOX or gemcitabine-NabP induction, respectively, seems to be a promising approach to minimize neurotoxicity while maintaining efficacy. Another option is to introduce maintenance drug(s) with different anti-tumoral actions. The recent example of olaparib in patients with BRCA mutated PDAC provides a promising proof-of-concept of a switch maintenance strategy in this setting.

Study Evaluating the Efficacy of a Double Immunotherapy Combined With Olaparib in Patients With Solid Cancers and Carriers of Homologous Recombination Repair Genes After Olaparib Treatment

Study Evaluating the Efficacy of a Double Immunotherapy Combined With Olaparib in Patients With Solid Cancers and Carriers of Homologous Recombination Repair Genes After Olaparib Treatment

Olaparib in Patients With Recurrent Ovarian Cancer Wild Type for Germline and Somatic BRCA 1 and 2 Genes: The MITO 31 Translational Study

Olaparib in Patients With Recurrent Ovarian Cancer Wild Type for Germline and Somatic BRCA 1 and 2 Genes: The MITO 31 Translational Study

Abstract CT025: Phase Ib study of adavosertib in combination with olaparib in patients with refractory solid tumors: Dose escalation

Abstract Background: Preclinical data suggest that adavosertib (AZD1775), a highly selective Wee1 inhibitor, enhances the antitumor effect of PARP inhibitors such as olaparib. The dose-escalation part of this Phase Ib study (NCT02511795) investigated the safety and tolerability of adavosertib plus olaparib in patients (pts) with refractory solid tumors to determine a maximum tolerated dose (MTD) and recommended Phase II dose (RP2D). Methods: Pts received adavosertib (QD or BID) for 3 consecutive days with 4 days off treatment (3/4), or 5 consecutive days with 2 days off (5/2), plus olaparib (BID) for 14 or 21 days of a 21-day cycle (Table). The MTD was the highest dose at which <1/3 of evaluable pts had a dose-limiting toxicity (DLT). DLTs were hematologic grade (gr) ≥4 AEs lasting >7 days, gr 3 thrombocytopenia with gr ≥2 bleeding, non-hematologic gr ≥3 AEs (excluding nausea, vomiting or diarrhea that responds to supportive care), liver function gr ≥3 AEs lasting >48 hours or changes consistent with Hy’s Law, or any other toxicity that disrupted dosing for >7 days. Results: 119 pts were treated (84 female; median age 59; most common primary tumor sites: ovary [21%], breast [16%], lung [12.6%]) (Table). The most common gr ≥3 AEs were anemia (n=28, 23.5%), neutropenia (n=26, 21.8%), and thrombocytopenia (n=20, 16.8%) (all grouped terms). The most common DLTs were thrombocytopenia (n=4) and neutropenia (n=4); two pts experienced both. There were 4 SAEs with an outcome of death, 1 was treatment related. ORR for the total population, cohort 4.2 and cohort 7.4 was 11.1%, 30.8% and 0%, respectively. DCR was 55.7%, 76.9% and 53.8%, respectively. PK and biomarker data will be presented. Conclusions: Treatment with adavosertib plus olaparib showed antitumor activity, mostly at the MTD/RP2D for the BID schedule, which was determined to be adavosertib 175 mg (3/4) for 2/3 weeks plus olaparib 200 mg BID. The RP2D for QD schedule was adavosertib 200 mg (3/4) for 2/3 weeks plus olaparib 200 mg BID. Summary of study cohortsCohortAdavosertib doseOlaparib doseAdavosertib schedule, daysOlaparib schedule, daysPatients, n (evaluable,* n)Patients with a DLT, n (%)Grade ≥3 AEs,† n (%)ORR, n (%)DCR, n (%)1125 mg BID (3/4)100 mg BID1–3/8–101–143 (2)01 (33.3)03 (100)2150 mg BID (3/4)100 mg BID1–3/8–101–144 (4)02 (50)1 (25)2 (50)3.1175 mg BID (3/4)100 mg BID1–3/8–101–144 (2)03 (75)03 (75)3.2150 mg BID (3/4)200 mg BID1–3/8–101–147 (5)04 (57.1)1 (14.3)5 (71.4)4.1175 mg BID (3/4)200 mg BID1–3/8–101–147 (7)04 (57.1)1 (14.3)4 (57.1)4.2175 mg BID (3/4)200 mg BID1–3/8–101–2114 (11)1 (9.1)9 (64.3)4 (30.8)10 (76.9)4.3175 mg BID (3/4)200 mg BID1–3/8–10/15–171–2114 (11)2 (18.2)13 (92.9)1 (7.7)7 (50)5175 mg BID (3/4)300 mg BID1–3/8–101–145 (5)1 (20.0)3 (60.0)2 (50)4 (100)6.1250 mg QD (5/2)200 mg BID1–5/8–121–217 (4)2 (50.0)6 (85.7)1 (20)1 (16.7)6.2200 mg QD (5/2)200 mg BID1–5/8–121–217 (5)2 (40.0)4 (57.1)01 (14.3)7.1250 mg QD (3/4)200 mg BID1–3/8–101–2116 (14)2 (14.3)12 (75)010 (62.5)7.2250 mg QD (3/4)200 mg BID1–3/8–10/15–171–214 (4)1 (25.0)3 (75)1 (25)3 (75)7.3300 mg QD (3/4)200 mg BID1–3/8–101–213 (3)1 (33.3)2 (66.7)007.4200 mg QD (3/4)200 mg BID1–3/8–101–2113 (12)1 (8.3)3 (23.1)07 (53.8)8.1200 mg QD (3/4)300 mg BID1–3/8–101–2111 (9)1 (11.1)4 (36.4)04 (40)*Evaluable patients received >75% of the planned dose of adavosertib and olaparib; †Common Terminology Criteria for Adverse Events. DCR, disease control rate; ORR, objective response rate Citation Format: Erika Hamilton, Gerald S. Falchook, Judy S. Wang, Siqing Fu, Amit Oza, So Karen, Esteban Rodrigo Imedio, Sanjeev Kumar, Lone Ottesen, Ganesh M. Mugundu, Juliann Chmielecki, Suzanne Jones, David R. Spigel, Bob T. Li. Phase Ib study of adavosertib in combination with olaparib in patients with refractory solid tumors: Dose escalation [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr CT025.

Abstract CT232: Phase I combination study of the CHK1 inhibitor prexasertib (LY2606368) and olaparib in patients with high-grade serous ovarian cancer and other advanced solid tumors

Abstract Background: Checkpoint kinase 1 (CHK1) plays a central role in replication fork stabilization and homologous recombination repair (HRR) through modulation of cell cycle checkpoints and phosphorylation of HRR proteins. BRCA-deficient cancers frequently upregulate CHK1 for protection of stalled replication forks. Prexasertib is an ATP-competitive inhibitor of CHK1. Addition of prexasertib to olaparib, an oral PARP inhibitor, may allow for combinatorial synergy and sensitization to PARP inhibition among tumors with de novo or acquired resistance. Methods: We conducted an open-label phase 1 study following a 3+3 design. Patients (pts) received a 7-day lead-in of olaparib alone (C0), followed by 28-day cycles with prexasertib administered on days 1 and 15 and olaparib on days 1-5 and 15-19 with starting dose of prexasertib at 80mg/m2 and olaparib at 200mg. The MTD was defined as the highest dose level at which less than 1/3rd of at least 6 pts experienced a DLT during C0+C1. Pharmacokinetic blood samples were obtained at C0, C1, and C2. Pts enrolled to the expansion phase of the study underwent tumor biopsies during C0 and on C1D16 after the combination for pharmacodynamic assessment of target effects on HRR. Patient-derived organoid cultures with functional assays for HRR proficiency and replication fork stability were conducted in parallel as an exploratory objective. Results: Twenty-one pts have been treated, 19 in the dose escalation phase. Three of 6 pts experienced DLTs at the starting dose and included Gr 3 neutropenia and Gr 3 febrile neutropenia. Lower doses for both agents were evaluated; the MTD is prexasertib at 70mg/m2 IV on days 1 and 15 in combination with olaparib at 100 mg PO BID D1-5 and 15-19. No DLTs were observed at this dose level. Drug-related adverse events occurring in ≥ 50% of pts included leukopenia, neutropenia, thrombocytopenia, anemia, and nausea. Three pts with BRCA1-mutant high-grade serous ovarian cancer (HGSOC) achieved PRs, two of whom had progressed on a prior PARP inhibitor. Tumor biopsies from pts in the expansion cohort demonstrated decreased RAD51 foci after prexasertib exposure. Pre-prexasertib patient-derived organoid cultures were successfully established and subjected to a DNA fiber assay to assess replication fork stability. The organoid derived from tumor from a non-responding patient had stable replication forks, whereas the organoid from a responding patient demonstrated baseline fork instability. Conclusion: Prexasertib in combination with an abbreviated course of olaparib has preliminary clinical activity in patients with BRCA-mutant HGSOC who have previously progressed on a PARP inhibitor. A functional assay for HRR in tumor biopsies indicates that prexasertib can compromise RAD51 focus formation, consistent with the role of CHK1 in RAD51 phosphorylation and filament formation. Preliminary data in patient-derived organoid cultures parallels that of clinical responses and confirms previously published data suggesting replication fork instability contributes to response to prexasertib. An expansion cohort in the BRCA-mutant, PARP inhibitor-resistant HGSOC population is being enrolled to further assess efficacy of the combination and to obtain additional pharmacodynamic determinants of response and resistance. Citation Format: Khanh T. Do, Sarah J. Hill, Bose Kochupurakkal, Jeffrey G. Supko, Courtney Gannon, Adrienne Anderson, Alona Muzikansky, Andrew Wolanski, Jennifer Hedglin, Kalindi Parmar, Jean-Bernard Lazaro, Joyce Liu, Susana Campos, Ursula A. Matulonis, Alan D. D'Andrea, Geoffrey I. Shapiro. Phase I combination study of the CHK1 inhibitor prexasertib (LY2606368) and olaparib in patients with high-grade serous ovarian cancer and other advanced solid tumors [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr CT232.

Abstract CT229: Olaparib in patients (pts) with previously treated, homologous recombination repair mutation (HRRm) or homologous recombination deficiency (HRD)-positive advanced cancer: Phase II LYNK-002 study

Abstract Background: Human cancers are associated with defects in DNA damage repair (DDR). Evidence suggests a key role for poly(ADP-ribose) polymerases (PARPs) in repairing certain DNA damage lesions. Olaparib (a PARP inhibitor) is approved for pts with germline BRCA1 and BRCA2-mutated breast and ovarian cancers, and pts with or without BRCA mutation in recurrent ovarian cancer. Mutations in HRR genes (HRRm; beyond BRCA1 or BRCA2) and HRD may sensitize tumors to respond to PARP inhibitors. Olaparib has also shown favorable ORRs in HRRm/HRD-positive (HRD+) cancers, including prostate and ovarian. Thus, this study (NCT03742895) aims to evaluate the use of HRRm/HRD+ as biomarkers of tumor-agnostic response to olaparib monotherapy. Methods: Eligibility for this open-label, Phase II study requires pts ≥18 years of age with a previously treated, histologically/cytologically confirmed, HRRm/HRD+ advanced solid tumor; who have failed, are intolerant to, or ineligible for all available standard of care therapies; with no disease progression during prior platinum-based treatment. At baseline, pts should also have measurable disease per RECIST v1.1 or Prostate Cancer Working Group (PCWG)-modified RECIST v1.1 (for pts with prostate cancer) without CNS metastases, ECOG PS of 0 or 1, and no persistent toxicities (CTCAE grade >2) from prior cancer therapy. Pts may have received any number of prior regimens. Newly obtained or archival tumor samples will be centrally evaluated using the Lynparza HRR Assay (under development at Foundation Medicine, Inc). Pts will be grouped into 2 cohorts: cohort 1 will include pts with any solid tumor type with a BRCA1 or BRCA2 mutation (excluding breast and ovarian cancers); cohort 2 will include pts whose tumor (any type) is BRCA1 or BRCA2 wild-type and HRRm and/or HRD+ as determined by loss of heterozygosity score. Pts will receive olaparib 300 mg orally BID until documented disease progression, unacceptable toxicity, or study withdrawal. Tumor imaging will be performed at baseline, with response assessments Q8W in the first year and Q12W thereafter, per RECIST v1.1 by BICR or PCWG-modified RECIST v1.1, both modified to follow ≤5 target lesions per organ (10 total). AEs will be graded using NCI CTCAE v4.0. The primary endpoint is ORR; the point estimate and 95% CI calculated using the Clopper-Pearson method will be provided. Summary statistics for key secondary efficacy endpoints of duration of response, OS, and PFS will be provided using the Kaplan-Meier method. Safety endpoints will be summarized. Approximately 370 pts will be enrolled (~84 in cohort 1 [BRCA1 and BRCA2 mutated]; ~174 HRRm and ~112 HRD+ in cohort 2 [BRCA1 and BRCA2 wild-type]). Enrollment is ongoing in 5 countries beginning December 12, 2018. Citation Format: David Hyman, Andrew Hendifar, Hyun Cheol Chung, Michele Maio, Alexandra Leary, Iben Spanggaard, Joon Rhee, Matt Marton, Menghui Chen, Suba Krishnan, Ronnie Shapira. Olaparib in patients (pts) with previously treated, homologous recombination repair mutation (HRRm) or homologous recombination deficiency (HRD)-positive advanced cancer: Phase II LYNK-002 study [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr CT229.

Real-world clinical outcomes of olaparib therapy in Chinese patients with advanced serous ovarian cancer treated in Macau.

BackgroundOlaparib has been approved as an active and maintenance therapy for patients with platinum‐sensitive, BRCA‐mutated high‐grade serous ovarian cancer (SOC). However, the efficacy and safety data is lack among Chinese ovarian cancer patients.AimThis real‐world study aimed to evaluate the effectiveness and safety profile of olaparib in patients from mainland China, where olaparib is currently unavailable.Methods and resultsThis single‐center, observational study included 65 patients with pathologically confirmed advanced serous ovarian cancer from Kiang Wu Hospital in Macau between December 2015 and September 2017. Progression‐free survival (PFS) and other endpoints (treatment response, disease progression, and adverse events) were evaluated. PFS was estimated using the Kaplan‐Meier method. The median treatment duration was 4 months (range, 1‐15). The median PFS for the overall population was 4.2 months (95% CI 2.7‐5.2), while those for patients with wild‐type BRCA1/2 and BRCA1/2 mutations were 3.1 months (95% CI 1.3‐4.6) and 5.3 months (95% CI 2.8‐7.1), respectively. The median PFS tended to be longer for patients on maintenance therapy (between 9.0 months [95% CI 1.4‐17.5] and 10.0 months [95% CI 2.5‐18.1]) than for those on active therapy (between 3.1 months [95% CI 2.1‐3.8] and 3.0 months [95% CI 1.4‐4.5]). Most patients (87.0%) experienced low‐grade adverse events; the most common of which were fatigue (49.0%) and nausea (35.0%).ConclusionOur findings demonstrate clinical benefit of olaparib to mainland Chinese patients with high‐grade SOC, particularly for patients with BRCA mutations and who require maintenance therapy.

Durvalumab in Combination with Olaparib in Patients with Relapsed SCLC: Results from a Phase II Study

PurposeDespite high tumor mutationburden, immune checkpoint blockade has limited efficacy in SCLC. We hypothesized that poly (ADP-ribose) polymerase inhibition could render SCLC more susceptible to immune checkpoint blockade. MethodsA single-arm, phase II trial (NCT02484404) enrolled patients with relapsed SCLC who received durvalumab, 1500 mg every 4 weeks, and olaparib, 300 mg twice a day. The primary outcome was objective response rate. Correlative studies included mandatory collection of pretreatment and during-treatment biopsy specimens, which were assessed to define SCLC immunephenotypes: desert (CD8-positive T-cell prevalence low), excluded (CD8-positive T cells in stroma immediately adjacent/within tumor), and inflamed (CD8-positive T cells in direct contact with tumor). ResultsA total of 20 patients were enrolled. Their median age was 64 years, and most patients (60%) had platinum-resistant/refractory disease. Of 19 evaluable patients, two were observed to have partial or complete responses (10.5%), including a patient with EGFR-transformed SCLC. Clinical benefit was observed in four patients (21.1% [95% confidence interval: 6.1%–45.6%]) with confirmed responses or prolonged stable disease (≥8 months). The most common treatment-related adverse events were anemia (80%), lymphopenia (60%), and leukopenia (50%). Nine of 14 tumors (64%) exhibited an excluded phenotype; 21% and 14% of tumors exhibited the inflamed and desert phenotypes, respectively. Tumor responses were observed in all instances in which pretreatment tumors showed an inflamed phenotype. Of the five tumors without an inflamed phenotype at baseline, no during-treatment increase in T-cell infiltration or programmed death ligand 1 expression on tumor-infiltrating immune cells was observed. ConclusionsThe study combination did not meet the preset bar for efficacy. Pretreatment and during-treatment biopsy specimens suggested that tumor immune phenotypes may be relevant for SCLC responses to immune checkpoint blockade combinations. The predictive value of preexisting CD8-positive T-cell infiltrates observed in this study needs to be confirmed in larger cohorts.

177Lu-PSMA-617 Therapy and Olaparib in Patients With Metastatic Castration Resistant Prostate Cancer

177Lu-PSMA-617 Therapy and Olaparib in Patients With Metastatic Castration Resistant Prostate Cancer

Maintenance Olaparib in Patients With Newly Diagnosed Advanced Ovarian Cancer

(Abstracted from N Engl J Med 2018;379:2495–2505) Standard-of-care therapy for patients newly diagnosed with advanced ovarian cancer consists of frontline cytoreductive surgery and adjuvant platinum chemotherapy. Approximately 70% of these patients have a relapse within 3 years.